Objectives: Self-description research on athletes with intellectual disabilities (ID) is under investigated. The specific aims in this paper are (a) to identify the differences in physical self-concept and body image by Unified Sports experiences, and (b) to investigate predictors of physical self-concept. Methods: Participants included 89 Special Olympics athletes who had Unified Sports experiences (USE, n = 43) and those without USE (n = 46). Demographic, anthropometric, self-description data were collected during the questionnaire interview and physical examination. Analyses included descriptive and regression modeling to determine differences in the psychological attributes by USE and best subsets of predictors of each physical self-concept construct. Results: The findings suggest that the participation of USE facilitated greater sport competence and there is no single predictor across the six physical self-concept constructs. Conclusion: The findings provide evidence that sports participation may have positive impacts on physical self-concept toward athletes with ID.